:root {
    --primary-color: #1a3c5e;
    --secondary-color: #3cb4b0;
    --accent-color: #ff7e3d;
    --bg-color: #f5f7fa;
    --text-color: #333;
    --light-text: #fff;
    --card-bg: #fff;
    --border-radius: 8px;
    --shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    --gradient: linear-gradient(135deg, var(--primary-color), #2e5c8e);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Roboto', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

header {
    background: var(--gradient);
    color: var(--light-text);
    padding: 20px 0;
    box-shadow: var(--shadow);
}

header .container {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.logo {
    margin-bottom: 10px;
}

.logo-text {
    font-family: 'Montserrat', sans-serif;
    font-weight: 900;
    font-size: 2.5rem;
    color: var(--light-text);
    letter-spacing: -1px;
}

.accent {
    color: var(--accent-color);
}

h1 {
    font-family: 'Montserrat', sans-serif;
    font-weight: 700;
    font-size: 2rem;
    margin-bottom: 5px;
}

.tagline {
    font-weight: 300;
    font-size: 1.1rem;
    opacity: 0.9;
}

.banner {
    background-color: var(--secondary-color);
    color: var(--light-text);
    text-align: center;
    padding: 15px 0;
}

.banner h2 {
    font-family: 'Montserrat', sans-serif;
    font-weight: 700;
    margin-bottom: 5px;
}

.banner p {
    font-weight: 300;
    opacity: 0.9;
}

main {
    padding: 40px 0;
}

.conversion-card {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    margin-bottom: 30px;
}

.primary-card {
    border: 2px solid var(--primary-color);
}

.card-header {
    background-color: var(--primary-color);
    color: var(--light-text);
    padding: 15px 20px;
}

.card-header h3 {
    font-family: 'Montserrat', sans-serif;
    font-weight: 700;
    font-size: 1.2rem;
    margin: 0;
}

.card-body {
    padding: 25px 20px;
}

.conversion-form {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 20px;
    align-items: center;
}

.input-group {
    margin-bottom: 15px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
    color: var(--primary-color);
}

.input-wrapper {
    position: relative;
}

input {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid #e1e5f0;
    border-radius: var(--border-radius);
    font-family: 'Roboto', sans-serif;
    font-size: 1rem;
    transition: border-color 0.3s;
}

input:focus {
    outline: none;
    border-color: var(--secondary-color);
}

.unit {
    position: absolute;
    right: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: #888;
}

.conversion-arrows {
    display: flex;
    justify-content: center;
    align-items: center;
}

#swap-btn {
    background-color: var(--secondary-color);
    color: var(--light-text);
    border: none;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    font-size: 1.2rem;
    cursor: pointer;
    transition: transform 0.3s, background-color 0.3s;
}

#swap-btn:hover {
    background-color: var(--accent-color);
    transform: scale(1.1);
}

.result-display {
    background-color: #f0f4f8;
    border-radius: var(--border-radius);
    padding: 20px;
    text-align: center;
    margin-top: 20px;
}

.result {
    font-family: 'Montserrat', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 5px;
}

.precision-note {
    font-size: 0.9rem;
    color: #666;
}

.tools-section h2 {
    font-family: 'Montserrat', sans-serif;
    text-align: center;
    margin-bottom: 30px;
    color: var(--primary-color);
}

.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.tools-grid .conversion-card {
    margin-bottom: 0;
}

.tools-grid .card-header {
    background-color: var(--secondary-color);
    padding: 10px 15px;
}

.tools-grid .card-body {
    padding: 15px;
}

.result-mini {
    background-color: #f0f4f8;
    border-radius: var(--border-radius);
    padding: 10px;
    text-align: center;
    font-weight: 500;
    color: var(--primary-color);
}

.conversion-table {
    margin-top: 40px;
}

.conversion-table h2 {
    font-family: 'Montserrat', sans-serif;
    text-align: center;
    margin-bottom: 20px;
    color: var(--primary-color);
}

.table-wrapper {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    background-color: var(--card-bg);
    box-shadow: var(--shadow);
    border-radius: var(--border-radius);
    overflow: hidden;
}

th {
    background-color: var(--primary-color);
    color: var(--light-text);
    text-align: left;
    padding: 12px 15px;
}

td {
    border-bottom: 1px solid #e1e5f0;
    padding: 12px 15px;
}

tr:last-child td {
    border-bottom: none;
}

tr:hover {
    background-color: #f0f4f8;
}

.info-band {
    background-color: var(--primary-color);
    color: var(--light-text);
    padding: 40px 0;
}

.info-band .container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.info-item {
    text-align: center;
}

.info-icon {
    font-size: 2.5rem;
    margin-bottom: 10px;
}

.info-item h3 {
    font-family: 'Montserrat', sans-serif;
    margin-bottom: 5px;
}

footer {
    background-color: #1a3c5e;
    color: var(--light-text);
    padding: 30px 0;
    text-align: center;
}

.logo-footer {
    margin-bottom: 20px;
}

.footer-content {
    opacity: 0.8;
}

.formula {
    margin-top: 10px;
    font-style: italic;
}

/* Button styles */
.button-group {
    display: flex;
    justify-content: space-between;
    gap: 10px;
    margin: 15px 0;
}

.btn {
    padding: 10px 20px;
    border-radius: var(--border-radius);
    font-family: 'Montserrat', sans-serif;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    flex-grow: 1;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.btn-sm {
    padding: 8px 12px;
    font-size: 0.85rem;
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--light-text);
}

.btn-primary:hover {
    background-color: #0f2d4d;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.btn-secondary {
    background-color: #e1e5f0;
    color: var(--primary-color);
}

.btn-secondary:hover {
    background-color: #d0d6e7;
    transform: translateY(-2px);
}

/* SEO content section */
.seo-content {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 30px;
    margin-top: 40px;
    box-shadow: var(--shadow);
}

.seo-content h2 {
    font-family: 'Montserrat', sans-serif;
    color: var(--primary-color);
    margin-top: 25px;
    margin-bottom: 15px;
    font-size: 1.4rem;
}

.seo-content h2:first-child {
    margin-top: 0;
}

.seo-content p {
    margin-bottom: 15px;
    line-height: 1.7;
    color: #555;
}

@media (max-width: 768px) {
    .conversion-form {
        grid-template-columns: 1fr;
    }
    
    .conversion-arrows {
        transform: rotate(90deg);
        margin: 10px 0;
    }
}